"When you get into a fitness rut, you're not getting the most out of your workout," says Greg Justice, an exercise physiologist in Kansas City and author of Mind Over Fatter. "Each one becomes less and less effective." Here, he explains how to tell if you're in a fitness funk—and how to get out of it.

You're Not Making Progress Anymore
Hitting a plateau with your fitness goals is a definite sign that you're stuck. "Say, for example, that you've been trying to run faster, but you keep running three miles in 35 minutes," says Justice. "That means that you're in a rut and you need to take action." His advice: Hire a personal trainer. Worried about price? Just one session will do the trick. "All it takes is one good consultation, and your trainer will likely be able to help you figure out how to get over the hump."

You Start Quitting Earlier
Imagine that your goal is to do three sets of reps on the leg press every other day. "If those three reps start seeming harder and harder and you begin ending at two reps, you're probably in a rut," says Justice. To inject more energy into your workouts, take a couple of days off. "People often burn out and don't allow themselves enough time to recover," he says. "So if you take a couple rest days, you may be surprised at how much easier it is to push yourself to the max when you return." Another option: Focus on your nutrition. Are you eating healthy foods? If you're eating tons of processed crap, it could be affecting your stamina.

You're Constantly Looking at Your Watch
If you check the time every few milliseconds, that means that you're not ever really getting into the deep workout zone, which is basically like the exercise equivalent of REM sleep (where the true magic happens). If that's the case, Justice suggests making a new playlist. "It could be that you're just really bored and need new music to pump you up," he says. If that doesn't work, you might want to try changing your workout routine entirely. "Try a new class or run outside if you've been running inside," he says. "Changing your surroundings in a big way can usually get you out of a rut."